Carbon emissions are closely related to human activities. China has become the largest carbon dioxide emitter in the world because of its extensive use of high-carbon energy. The price paid by the deterioration of China's environmental quality is about 3%-8% of the total GDP yearly, and environmental sustainability is declining. Therefore, it is urgent to play the role of environmental regulation and introduce green funds to lower the carbon cycle and green development. Therefore, based on the data from 30 provinces from 2004 to 2019, this paper uses a spatial econometric model to consider the dynamic impact of environmental regulation intensity and green financial development on regional environmental sustainability. The research shows that:(1) China’s local environmental sustainability shows a noticeable spatial agglomeration effect, which is significant and spatially autocorrelated and clustered. (2) Based on the national level, the improvement of environmental regulation intensity will significantly improve regional environmental sustainability, and the development of green finance will also significantly improve regional environmental sustainability. Additionally, the intensity of environmental regulation has a significant positive spatial spillover effect, which may increase environmental sustainability in neighboring provinces. The impact of green financial development on environmental sustainability also has a significant positive spatial spillover effect. (3) Based on the provincial level, environmental regulation and green financial development have a significant positive impact on the environmental sustainability of each region, with the most significant impact on the western region, the northeast and central regions in the middle, and the east coefficient being the smallest. Based on the above conclusions, this paper puts forward the "5R" model to comprehensively promote the sustainable improvement of the regional environment.